Research Co-ordination Meeting on Recent Developments in the Use of Nitrogen-15 in Soil-Plant Studies Sofia, Bulgaria, & Joint FAO/IAEA Division of Atomic Energy in Food and Agriculture. (1971). Nitrogen-15 in soil-plant studies: Proceedings. International Atomic Energy Agency.

Research Co-ordination Meeting on Recent Developments in the Use of Nitrogen-15 in Soil-Plant Studies Sofia, Bulgaria, and Joint FAO/IAEA Division of Atomic Energy in Food and Agriculture. Nitrogen-15 in Soil-plant Studies: Proceedings. Vienna: International Atomic Energy Agency, 1971.

Research Co-ordination Meeting on Recent Developments in the Use of Nitrogen-15 in Soil-Plant Studies Sofia, Bulgaria, and Joint FAO/IAEA Division of Atomic Energy in Food and Agriculture. Nitrogen-15 in Soil-plant Studies: Proceedings. International Atomic Energy Agency, 1971.